Spirit level



May' 4, 19.26.

F'ilec June '7I 1924 2 Sheets-Sheet l Hawai/5,

May 4 1926. 1,583,489

. A. L. PERRINE SPIRIT LEVEL Filed June 7, 1924 l 2 Sheets-Sheet 2 Patented y'li/lay 4, 1926. UNITED STATES PATENT .-oFFicE.

ARTHUR L. PERRINE, OF CLEVELAND HEIGHTS, OHIO.

ASPIRIT LEVEL.

Application nl'ed I une 7,

tain new and useful Improvement in 'a Spirit 1 vantageoiisly,

, suitable electric lamps.

Level, of which the following and exact description, reference being to the accompanying dra-wings.

This invention relates to spirit levels, -such as used in building construction. ."Ihe essential object is to provide foi` illuminating the level tubes of such instruments with Another object is to provide a compact lighting system for a spirit level which will not detract from the appearance ofthe article. Furtherobjects include the provision of a cheaply manufactured illuminated spirit level' wherein standard electric iixtures such for instance as are used in flash lights may be used adwith a minimum amount of change in the standard construction of the level itself.

l Other features andobjects tion will become apparent in scription of my invention which pertains to the accompanying drawings. The essential characteristics thereof will be defined and summarized in the claims. l

In the drawings Fig of my illuminated spirit 'level; Fig. 2 1s -a perspective showing the adaptation for connecting the batteryl to the lighting system and securing it in t e level; Fig. 3 is a transthrough the battery socket as 'indicated by the lines 3-3 on Fig. 1; Fig. 4 is a similar sectional view showing battery terminal clips, as indicated by the; line 4 4 on Fig. 1; Fig. 5 is diagram;

is a full, clear, had

of my invenverse section a wiring 'Fig 6 is a fragmentary plan of one of the illuminated tuba units, and the electric switch, portions of the cover plate being broken away to disclose these parts; Fig.

is a transverse cross section as indicated by the line 7--7l on Fig. 6 showing the bulb supporting means; Fig. 8 is a similar cross section as indicated by the line 8-8 on Fig. 6 showing the switch; Fig. 9 is a transverse cross section as indicated by the line 9 9 on Fig. 1. l

I propose to position the battery in one end of the level in such a manner that the insertion of the battery into the aperture provided for it will establish the desired electric connection. The preferred method of the further de- 1 is ya side elevation 1924. Serial No. 718,648.`

providing for a wire conduit in a metal levelconsists of utilizingthe usual marginal stif-` fening webs, one of which will be grooved and adequately covered and which will communicate with covered recesses surrounding v.

'units for containing the as well as the end faces 7 being formed as near as possible'into a perfect plane. Horizontal spirit tubes 8 and 9 each containing fluid and an air space or bubble 10, 4are shown as supported in cylindrical holders "11. The axes of each pair of tubes describe opposed, that is .to'say convex curves. purpose of this arrangement is to provide for more quickly ascertaining the approximate level of the plane surfacevnearest t e tube. For instance, when the surface 6 of the level frame rests upon' the surface of a building member to be leveled the operator watches the the bubble therein more quickly finds the central region of the tube. The use of the vertically placed tubes 15 and 16 is substantially the same, except that these are use for vertical leveling, that is to say in place ofa plumb line. In this use whichever of the tubes happens to be uppermost as the operator picks upl the level will give the desired reading. l

For the above reasons II find it most desirable to illuminate yall of the spirit tubes as near thecenter of the convex side of each of the tubes as possible'. Accordingly I show a lamp 20 partly within the holderA 11 and between the pair of horizontal tubes. Each of the vertical leveling tubes are illuminated by light bulbs 22 and 23, so placed The lower of the tube 8, since that in use the bulbs will be nearest the surend wall portions of the level frame comy pletes the receptacle. Spring clips -27 and Z8 upon the floor of the receptacle are spaced apart therefrom by suitable insulating Astrips and washers 29 an 30.- The spring termi-n nals 'b and b engage the spring clips when the battery is lowered into the receptacle.

A closed The battery and terminals are held in place by a cover plate 31 which fits a groove 32 in the frame and may be held in place by a tongue 33 on the plate and a screw 34. The wall 22 is slotted at for admitting the terminal wires, and the bottom portion of the slot reaches substantially the depth of a groove 36 along the web 37 of the frame. This groove ext-ends practically the entire length of the web and has shoulders at 38 and 39 for better receiving andsupporting a cover plate 40. Adjacent the groove and surrounding the level tubes are provided receptacles substantially similar to that shown in Fig. 6 and which are formed by the side walls 41 and 42, the webs and a floor or rear wall portion 43.v

A convenient form of supporting the spirit tubes consists of a cylindrical barrel 45 carried between the ribs 37 and 38 and supported thereby, which barrel carries a shorter inner barrel designated 46. This latter barrel may support at its ends transparent plates as indicated at 47 in Fig. l, for protecting the spirit tube. I preler to provide apertures as indicated at 50 and 51 in both these barrels and slightly back of the apertures I provide a socket 52 for receiving a small electric light bulb. This socket may comprise a tubular strip of metal as shown in Fig. 7 at 53 having suitable screw threads formed therein for receiving the shank of the bulb and having a looped attachedportion 54. The loop receives the end of a conductor wire which is clamped therein by a screw 55. The return circuit from the lamp may be established by another spring elip 57 having a terminal loop and attaching screw similar to that of the socket.

As shown in Fig. 5, the lead 60` Jfrom the battery B terminates in a switch 61. A lead 56 from this switch returns to thebuss Wire 58, to which the lamps 20, 22 and 23 are connected in parallel, the circuit being completed by the buss wire 66.

The switch as shown in Figs. 6 and 7 preferably consists of a pair of leaf spring members and 66 secured to the floor 43. The upper leaf carries a button 67 which 'projects through a (lished region of the cover plate 68. In this position the control switch does not detract from the otherwise balanced appearance of the level and is in the most likely place where the fingers of the operator would grasp the instrument, when applying it to his work.

The cover plates for all the units are substantially alike and are secured along one edge to the web 37 by one or more screws 72 while the other edge is bent to lie beneath the edge of the strip 40. Suitable screws may hold the strip in place which may engage bosses 7l adjacent one corner of each receptacle as shown. The end of the frame unoccupied by a battery may be closed as at 75 to give the level a Symmetrieal and balanced appearance.

It will be seen that I have provided an illuminated level construction which may be easily adapted to levels now in use and which will not detract from the appearance thereof. It will be seen further that I have fitted the component parts of the lighting circuit into receptacles forming partv ot the frame construction in such a manner as to aiiord the most ample protection against accidental damage. The lamps are most advantageously located with respect to the level tubes and are so concealed by the tube holding frames that the operators eyes will be shielded from the direct glare from the filament.

Having thus described my invention, I claim:

l. In combination with a metal lever frame substantially I shaped in cross section, a tubular member carried by the web of the I, a spirit level tube positioned thereacross said tubular member having an opening in the side wall thereof, a cover plate forming with the ianges of the web a compartment surrounding the tubular member, said plate having an opening fitting yover the tubular member whereby the tubular member is opened to sight at either side of the trame, a light bulb mounted in the compartment. adjacent the opening in the tubular member, and means for supplying power to the bulb.

2. In a level, a frame substantially I shaped in cross section, a cylindrical hollow boss having an opening in the side thereof and carried by the web of the I, a spirit level positioned across the boss, ribs eX- tending transversely of the frame and rising from the web at either side of the boss,

a cover extending on either side of the flanges on one side of the I and resting on the ribs to form with the web a substantially closed'compartment, said cover hav ing an opening registering with the boss and a light bulb carried in the compartment adapted to illuminate the level through the opening in the boss.

3. A level having a frame substantially I shaped in cross section, ribs rising from the webs of the I, and a plate resting thereon and Secured to the frame to form with the web and ribs a compartment, a tubular meml20 ply power to the light.

.tween the flanges,

10 nate the tube, a groove 4. In combination with a metal levelframe, said frame havin a web and flanges extending transversely t ereof, means associated wlth the Web for supporting a spirit level tube and a compartment adjacent the tub'evsupporting means comprising the web and flanges and a cover plate extending bea light bulb mounted in the compartment and arranged to illumifor a conductor wire adjacent one of the flanges and communicating with the compartment, a battery carried ina separate compartment, said latter compartment also communicating with the groove, a cover plate for the groove, said cover plates being in overlapped relation whereby the outer one serves .to hold the inner in place.

In testimony whereof, I hereunto affix my signature.

i ARTHURA L. PERRINE. 

